Daily Vitamin D Does Not Improve or Prevent Anemia

Patients taking vitamin D or placebo had similar changes in hemoglobin levels.

Taking a daily vitamin D supplement does not prevent or improve anemia in patients with advanced heart failure, including those with concurrent chronic kidney disease (CKD), according to new study findings.

In a secondary analysis of the EVITA (Effect of Vitamin D on Mortality in Heart Failure NCT01326650) trial, Armin Zittermann, PhD, of Ruhr University Bochum, Georgstra in Germany and his team studied 172 patients with congestive heart failure and low circulating 25-hydroxyvitamin D levels (below 75 nmol/L) who were randomly assigned to receive daily vitamin D3 (4000 IU cholecalciferol drops, 85 patients) or matching placebo (87 patients) for 36 months. Initially, 17.2% and 10.6% of each group, respectively, had anemia (hemoglobin [Hb] below 12 g/dL for women and 13 g/dL for men). Over 36 months, the proportion of anemic patients grew to 32.2% and 31.8%, respectively, according to results published in the Nutrition Journal. Hb levels between the groups differed by -0.5 g/dL.

A subset of patients -- 26 in the vitamin D group and 23 in the placebo group -- also had stage 3 to 4 CKD. Anemia prevalence among these patients rose from 23.1% and 21% at baseline to 50% and 47.8%, respectively. Again, the investigators found no meaningful between-group difference in Hb levels.

The causes of anemia were iron deficiency, folate or B12 deficiency, CKD, inflammation, or unknown. None of the 172 patients received erythropoietin or iron during the trial.

“Our data challenge the clinical relevance of vitamin D supplementation to increase Hb levels,” Dr Zitterman and his colleagues stated. The results disagree with a recent meta-analysis on the subject purporting vitamin D benefits, but agree with several other randomized controlled trials.